Grain refinement in laser remelted Mg-3Nd-1Gd-0.5Zr alloy

doi:10.1016/j.scriptamat.2020.03.006

Scripta Materialia

Volume 183, 1 July 2020, Pages 12-16

https://doi.org/10.1016/j.scriptamat.2020.03.006 Get rights and content

Abstract

Columnar grains are normally favoured with the high cooling rate and steep thermal gradient in laser-based additive manufacturing. Here, we demonstrate that fine, fully equiaxed grains can be achieved in Mg-3Nd-1Gd-0.5Zr (EV31) alloy by laser surface remelting. The grains in the melt pool are remarkably refined from 74 µm to 3.5 µm, which can be attributed to the growth restriction effect, i.e. the constitutional supercooling formed by Zr solute during solidification in combination with the high cooling rate imposed by laser surface remelting. This novel finding could be applied for the control of grain morphology and alloy design for additive manufacturing applications.

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Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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Grain refinement in laser remelted Mg-3Nd-1Gd-0.5Zr alloy

Abstract

Graphical abstract

Section snippets

Declaration of Competing Interest

J. Alloys Compd.

J. Cryst. Growth

J. Manuf. Process

Scr. Mater.

Acta. Mater.

Acta. Mater.

Scr. Mater.

Mater. Sci. Eng. A

Corros. Sci.

Mater. Des.

Acta. Mater.

J. Light Met.

Acta. Mater.

Metall. Mater. Trans. A

Metall. Mater. Trans. A

Acta Mech.